Utility of Trichoscopy in Various Types of Alopecia - A Cross-Sectional Study

Alopecia is one of the most common reasons for consulting dermatologists, and the clinical diagnosis can become confusing. In light of the inclination of patients and doctors toward non-invasive diagnosis, along with the vogue of non-invasive diagnostic modalities, trichoscopy has become a promising tool.

To study various dermoscopic patterns of alopecia.

After obtaining informed consent, this cross-sectional study was conducted among 100 patients with alopecia attending a tertiary health care center. A detailed history and clinical photographs were taken. Relevant investigations were done whenever indicated. Dermoscopy was done using illuco IDS- 1100 with 10x magnification. Statistical analysis used: Data was analyzed using SPSS 22 version software. The chi-square test, Kolmogorov-Smirnov test, and Shapiro-Wilk test was used for assessment with a significant P-value of < 0.05. Kappa statistics were used to assess agreement between the two modalities.

Overall, vellus hair (65%) and yellow dots (65%) were the most common findings among all types of alopecia. The most common findings on trichoscopy in androgenetic alopecia were vellus hair (90.48%); in alopecia areata, vellus hair, and exclamation mark hair (86.67% each); in tinea capitis, corkscrew hair, and black dots; and in trichotillomania, splaying of hair. Discoid Lupus erythematosus had absent follicular opening, scaling, and perifollicular pigmentation. Clinical and dermoscopic diagnoses were significantly associated with a kappa agreement of 0.776 (i.e., substantial agreement). Out of 15 cases of difficult-to-diagnose alopecia, further investigations showed that dermoscopic diagnosis was accurate in 7 cases (46.67%).

Trichoscopy is a reliable, non-invasive, and faster method of diagnosis in ambiguous cases of alopecia.